Quiet please!

A loud ventilation system was a headache for the teachers and the pupils at the Backaskolan in Malmö, Sweden. Then came Martin Jörgensen, a technician from Caverion, to quiet things down.

September 2017

The Backaskolan in Malmö is actually a pretty idyllic place to go to school. The school is situated in Sege Park, offering its 250 pupils a bit of nature in the middle of the Swedish metropolis. But things were anything but idyllic in the classrooms in recent months, with teachers and pupils regularly leaving the building in the afternoon with their heads buzzing. At fault was not any kind of difficult subject matter, but the loud ventilation system. It had seen better days and was as noisy as any steamship, making teaching almost impossible.

Retrofit with RadiFit

The school administrators were aware of the problem, but were at first unable to find anybody who could solve it. Not knowing how to fix the problem, various service providers rejected the job. Only Martin Jörgensen was able to help. He is a technician with Caverion Sverige AB, and when his facility management coworker contacted him with the request from the school in Malmö, he took a close look at the droning ventilation system. “The fans were out of balance,” he recalls. “That made them vibrate, which caused the loud noise.” It quickly became clear to Jörgensen that replacing the fans was the only way to quiet things down. So he contacted Jan Sörensen at ebm-papst in Sweden. “As I always do in cases like that, I called Jan. He suggested two possible products, and I decided on the RadiFit centrifugal fans,” recalls Jörgensen. “The previous fans were also double inlet fans, and the dimensions were a good fit as well.”

No vibrations, no noise

Now two RadiFit fans make sure things stay quiet in the Backaskolan. “Their offset blades reduce noise emissions,” says Sörensen. “Their mountings are soundproofed, and the impeller-rotor unit is dynamically balanced. That minimizes structure-borne noise and ensures low vibration levels. With their scroll housings and backward-curved blades, the units also facilitate an ideal pressure increase and high efficiency at high pressures. That keeps the classrooms dependably ventilated.

Silence sounds so good

Fitting in the new fans Martin Jörgensen had to be quiet flexible. (Photo | Martin Jörgensen)

Replacing the fans was child’s play for Martin Jörgensen because they can also be mounted without a flange. “One of the fans installed a bit too high for the existing opening, so I just mounted it without a flange and that worked just fine,” says the experienced technician. “That’s how it’s always been with fans from ebm-papst. They’re easy to install; I’ve never had any problems.” He was able to start up the new RadiFit fans on the school’s roof quickly and easily using their central terminal area for different connections, and without having to make any parameter settings. He is not the only one who is happy with the results. “After we restarted the ventilation system with the new fans, I went to see the teachers in the classroom,” recalls Jörgensen and has to laugh. “At first they couldn’t believe the system was even running, because you couldn’t hear anything anymore.” Obviously everybody is relieved and looking forward to days of teaching without headaches — at least not from the ventilation system.